This study evaluated how feeding colostrum- or a colostrum-milk mixture for 3 d postnatal affects plasma glucagon-like peptide-2 (GLP-2), serum insulin-like growth factor-1 (IGF-1), and small intestinal histomorphology in calves. Holstein bulls (n = 24) were fed colostrum at 2 h postnatal and randomly assigned to receive either colostrum (COL), whole milk (WM), or a 1:1 COL:WM mixture (MIX) every 12 h from 12 to 72 h. A jugular venous catheter was placed at 1 h postnatal to sample blood frequently for the duration of the experiment. Samples were collected at 1, 2, 3, 6, 9, 11, and 12 h. Following the 12-h meal, blood was collected at half-hour intervals until 16 h and then at 1-h intervals from 16 to 24 h. A 27-h sample was taken, then blood was sampled every 6 h from 30 to 60 h. Again, blood was taken at half-intervals from 60 to 64 h, then at 65 and 66 h, following which, a 2-h sampling interval was used until 72 h. Plasma GLP-2 (all time points) and serum IGF-1 (at time points: 1, 6, 12, 18, 24, 36, 48, and 72 h) were both analyzed. Duodenal, jejunal, and ileal tissues were collected at 75 h of age to assess histomorphology and cellular proliferation. Feeding COL, rather than WM, increased plasma GLP-2 by 60% for 2 h and tended to increase GLP-2 by 49.4% for 4 h after the 60-h meal. Insulin-like growth factor-1 area under the curve (from 12 to 72 h) tended to be 27% greater for COL than WM calves but was otherwise unaffected by treatment. Ileal crypts tended to proliferate more with MIX than WM, whereas ileal crypt proliferation did not differ for COL compared with MIX or WM and was not different between treatments in the proximal jejunum. Villi height was increased 1.8 and 1.5× (COL and MIX vs. WM) in the proximal and distal jejunum, respectively, whereas MIX duodenal and ileal villi height tended to be 1.5 and 1.4× that of WM. Crypt depth did not differ in any region. Surface area of the gastrointestinal tract was reduced for WM by 60 and 58% (proximal jejunum) and 38 and 52% (ileum) relative to COL and MIX and was 54% less than MIX in the distal jejunum. Overall, extended COL feeding minimally increased plasma GLP-2 and serum IGF-1 compared with WM feeding. As COL and MIX similarly promoted small intestinal maturation, feeding calves transition milk to promote intestinal development could be a strategy for producers.

中文翻译：

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产后3天喂初乳或1：1初乳：牛奶的混合物可增加小肠发育，并且对荷斯坦公牛犊的血浆胰高血糖素样肽2和血清胰岛素样生长因子1的浓度影响最小。

这项研究评估了在出生后3 d喂养初乳或初乳混合物如何影响血浆胰高血糖素样肽2（GLP-2），血清胰岛素样生长因子1（IGF-1）和小肠组织形态。小牛。荷斯坦公牛（n = 24）在出生后2小时接受初乳喂养，并从12到72每12小时随机分配一次接受初乳（COL），全脂牛奶（WM）或1：1 COL：WM混合物（MIX） H。在出生后1小时放置一个颈静脉导管，以便在实验过程中经常抽取血液。在1、2、3、6、9、11和12小时收集样品。进餐12小时后，每隔半小时采集一次血液，直到16小时，然后从16到24小时每隔1小时采集一次血液。进行27小时的采样，然后从30到60小时每6小时采样一次血液。同样，以半间隔60至64小时采血，然后在65和66 h，之后使用2 h采样间隔，直到72 h。血浆GLP-2（所有时间点）和血清IGF-1（时间点：1、6、12、18、24、36、48和72小时）均经过分析。在75 h时收集十二指肠，空肠和回肠组织，以评估组织形态学和细胞增殖。进食COL而非WM可使60小时饭后4小时血浆GLP-2升高60％，并倾向于4小时内GLP-2升高49.4％。曲线下的胰岛素样生长因子-1面积（从12到72 h）倾向于比WM犊牛高27％，但不受治疗影响。与MIX或WM相比，MIX的回肠隐窝倾向于比WM增殖更多，而回肠的回肠隐窝增殖与MIX或WM相比没有差异，并且在近端空肠治疗之间也没有差异。绒毛高度分别提高了1.8和1。空肠近端和远端空肠分别为5倍（COL和MIX vs. WM），而MIX的十二指肠和回肠绒毛高度往往是WM的1.5和1.4倍。地穴深度在任何区域都没有差异。相对于COL和MIX，WM的胃肠道表面积减少了60％和58％（近端空肠）以及38％和52％（回肠），并且比远端空肠减少了54％。总体而言，与WM喂养相比，延长的COL喂养对血浆GLP-2和血清IGF-1的增加作用最小。由于COL和MIX相似地促进了小肠的成熟，所以给小牛喂食过渡乳以促进肠的发育可能是生产者的一项策略。相对于COL和MIX，WM的胃肠道表面积减少了60％和58％（近端空肠）以及38％和52％（回肠），并且比远端空肠减少了54％。总体而言，与WM喂养相比，延长的COL喂养对血浆GLP-2和血清IGF-1的增加作用最小。由于COL和MIX相似地促进了小肠的成熟，所以给小牛喂食过渡乳以促进肠的发育可能是生产者的一项策略。相对于COL和MIX，WM的胃肠道表面积减少了60％和58％（近端空肠）以及38％和52％（回肠），并且比远端空肠减少了54％。总体而言，与WM喂养相比，延长的COL喂养使血浆GLP-2和血清IGF-1的增加最小。由于COL和MIX相似地促进了小肠的成熟，所以给小牛喂食过渡乳以促进肠的发育可能是生产者的一项策略。